Circuit Judge Rick Knapp said Friday nothing would stop Joseph Walsh from preying on another child.

Nothing but prison.

"You have put us in a position where we simply have to lock you up," the judge said before he handed down four life sentences -- one for each of Walsh's latest victims.

Walsh, 44, was sentenced under Oregon's three-strikes law for sex offenders. His convictions in 1993 and 2001 preceded his most recent case, decided by Washington County jurors in April.

A jury convicted him on 19 counts related to the sexual abuse of four boys. The Tigard man was found guilty of first-degree sexual abuse, using a child in a display of sexually explicit conduct, encouraging child sex abuse, unlawful contact with a child, luring a minor and attempted delivery of marijuana to a child.

Knapp said Friday a presentencing investigation noted that Walsh had once admitted to abusing 60 or more victims. The judge said he believed that was perhaps a low estimate.

Defense attorney Bill Redden asked for a sentence of 25 years in prison. If Walsh survived his incarceration, Redden said, he'd be nearing 70 at the end of that term. There was no point in warehousing Walsh longer than that, the attorney argued.

Knapp, however, did see a point. Walsh had demonstrated that nothing would prevent him from committing another crime, the judge said. He followed the state's recommendation and imposed the life sentences, which carry no chance for parole.

Joseph Edgley WalshWCSO

Authorities said Walsh met his victims through their parents, who took pity on him for his fictional tale about losing his wife and child in an accident. He won the boys' friendship through games and gifts and camping trips.

One of the boys told investigators, "He was like a really good friend. But he wasn't. ... He tricked us."

The case came to light when a father found his young stepson in the back of a truck with Walsh and became suspicious.

If Walsh were ever free, she said, no family would ever be safe from him.

"Every once in a while, a person's true nature becomes abundantly apparent," Johnson told the court. "There is no other purpose that he serves than to seek out and destroy young men."

During these comments and those of a mother of one of the victims and those of the judge, Walsh appeared calm. Dressed in an orange jail jumpsuit, he peered out of the courtroom window at blue sky and treetops.